Keyed anesthetic vaporizer filling system

ABSTRACT

A system for facilitating the delivery of a liquid anesthetic agent from an anesthetic bottle to an anesthetic vaporizer. The system includes a bottle adapter, an anesthetic bottle and a filler arrangement positioned on the anesthetic vaporizer. The bottle adapter and filler arrangement each include a keyed configuration such that only the correct type of anesthetic agent can be emptied into the anesthetic vaporizer. The bottle adapter includes an adapter valve assembly that engages a filler valve assembly contained within the filler. The dimensions and arrangement of the adapter valve assembly and the filler valve assembly insure anesthetic agent is delivered to the anesthetic vaporizer only when the anesthetic agent can safely flow from the anesthetic bottle to the anesthetic vaporizer.

CROSS-REFERENCE TO RELATED APPLICATION

The present application is based and claims priority to U.S. patentapplication Ser. No. 10/607,433, filed on Jun. 26, 2003, now U.S. Pat.No. 6,817,390, which is a continuation of prior application Ser. No.10/099,647, filed on May 15, 2002, now issued as U.S. Pat. No.6,585,016.

BACKGROUND OF THE INVENTION

The present invention generally relates to a system for transferring aliquid anesthetic agent from an anesthetic bottle to an anestheticvaporizer. More specifically, the present invention relates to ananesthetic vaporizer filling system that includes a unique valvearrangement and keyed engagement system that prevents the anestheticagent from being released to atmosphere during filling and insures thatonly the desired type of anesthetic agent can be discharged into theanesthetic vaporizer.

Anesthetic agents are typically volatile substances with relatively lowboiling points and high vapor pressures. Anesthetic agents can beflammable and explosive in both their liquid and vapor states. Further,inhalation of vapor by healthcare personnel in the area near where theanesthetic agent is being used can cause drowsiness. An anesthetic agentis administered to a patient during anesthesia by means of an anestheticvaporizer. The agent is supplied to the patient from an internal sumpwithin the vaporizer as a vapor, while the agent is stored within thesump as a liquid. The anesthetic agent is typically mixed with oxygenand nitrous oxide prior to its delivery to the patient for inhalation.

Devices and filling systems have been designed for the transfer of theanesthetic agent from a supply container, such as an anesthetic bottle,to the vaporizer sump through a closed system that minimizes the escapeof anesthetic gas to the atmosphere. These devices are designed so thatduring set-up and disassembly procedures, the anesthetic bottle is notopen and exposed to atmosphere.

One example of such a system is shown in the Grabenkort U.S. Pat. No.5,505,236. In this patent, the filling system lacks implementation of afiller probe seal, which in turn forces the implementation of a fillvent. The fill vent is required to prevent increased vapor pressurewithin the sump and filling system from causing egress of anestheticagent between the filler probe (bottle) and filler receiver (vaporizer).As a result, the fill vent allows release of anesthetic vapor toatmosphere during the filling process (most notably when filling avaporizer with dry sump and wick). Further, the anesthetic bottleincludes a plunger that is biased by a first spring. When the anestheticbottle is pressed into the filler of the anesthetic vaporizer, theplunger contacts the outer surface of an inlet valve member that in turnis biased to a closed position by a second spring. The first and secondsprings are configured such that the second spring holding the inletvalve member is weaker than the first spring biasing the plunger in theanesthetic bottle. This configuration of springs insures that the inletvalve member opens prior to anesthetic agent leaving the anestheticbottle. Therefore, the relative spring strengths of the pair of springsin the Grabenkort reference are critical to insure that the anestheticagent is not released to atmosphere. If the strength of either springchanges after repeated use, or if one of the springs is not properlycalibrated, anesthetic vapor could be released to atmosphere. Thissystem, therefore, has several drawbacks that need to be addressed.

Presently, many types of anesthetic agents are available for use duringanesthesia. These anesthetic agents include, but are not limited, to:Enflurane, Halothane, Isoflurane and Sevoflurane. Each of theseanesthetic agents has different properties and vaporizers are typicallydesigned to deliver the anesthetic agents differently depending upon theproperties of the anesthetic agent. Therefore, it is important that onlythe correct type of anesthetic agent is delivered to the vaporizer.

Currently, the International Standardization Organization (ISO) hasdeveloped standard 5360:1993 that mandates the inclusion of a pair ofprotrusions on an anesthetic agent bottle. The standard calls for aspecific angle between the protrusions around the bottle that is basedupon the type of anesthetic agent contained within the anestheticbottle. Because the anesthetic container for each type of anestheticagent has its own set of protrusions and color, and because acorresponding connector device for the anesthetic bottle fits only thetype of vaporizer designed for that type of anesthetic, the probabilityof inadvertently using the wrong type of anesthetic in a vaporizer hasbeen greatly reduced.

Although the anesthetic bottle may include protrusions specificallypositioned based on the type of anesthetic contained within the bottleand can be emptied by keyed connector tubes, typical anesthetic bottlesdo not include a valve arrangement that can be used to prevent loss ofthe anesthetic agent to atmosphere during filling. Further, the keyedconnector tubes are of a small size which reduce the rate of filling thevaporizer, and require manual operation of mechanisms to retain thekeyed tubes in the vaporizer while filling, and to operate valving inthe vaporizer to receive the anesthetic from the keyed connector tubes.Further, the keyed connector tubes themselves contain no valving toprevent loss of anesthetic vapor from the bottle when the bottle is notconnected to the vaporizer, or the loss of liquid from the bottle if thebottle is inverted while not connected to the vaporizer. Further, due tothe horizontal nature of the receiving ports in vaporizers for suchkeyed connector tubes, small amounts of liquid anesthetic persist in thetubing when the keyed connector tubes are disconnected from thevaporizer. This liquid anesthetic is then lost, since it is not retainedeither in the vaporizer or the keyed connector tubes.

Therefore, a need exists for an anesthetic vaporizer filling system thatallows a bottle adapter having a unique valve assembly to be attached tothe anesthetic bottle. Further, a need exists for a system having aspecifically configured filling station that interacts with the bottleadapter to insure that the anesthetic agent is not released toatmosphere during the filling procedure. Further, a need exists for thefilling station of the anesthetic vaporizer to have a uniqueconfiguration that receives only a specified type of anesthetic agent.

SUMMARY OF THE INVENTION

The present invention relates to a filling system for use in thedelivery of a liquid anesthetic agent from an anesthetic bottle to theinternal sump of an anesthetic vaporizer. The filling system includes akeyed registration system such that only the desired type of anestheticagent can be dispensed into a particular anesthetic vaporizer. Further,the filling system of the present invention minimizes the amount ofanesthetic agent released to atmosphere during the filling sequence.

The anesthetic vaporizer filling system of the present inventionincludes a bottle adapter that is configured for attachment to ananesthetic bottle. The bottle adapter includes internal threads that areconfigured to receive the threaded neck of the anesthetic bottle inconformance with the ISO 5360:1993 standard. The bottle adapter includesa pair of receiving slots positioned around its outer circumference thatreceive protrusions formed on the anesthetic bottle in conformance withthe ISO 5360:1993 standard. The receiving slots insure that each bottleadapter is attachable only to a single, specific type of anestheticagent.

The bottle adapter of the present invention is formed from nylon andcolored in accordance with the ISO standard colors for anestheticagents, in conformance with the ISO 5360:1993 standard. The color of thebottle adapter, and matching colored features adjacent to the filler onthe vaporizer, such as covers and labels, further insure that the propertype of anesthetic agent is being delivered.

The bottle adapter includes a keyed section used to insure that only asingle, correct bottle adapter can be used with an anesthetic vaporizer.The keyed section includes a pair of indexing ridges formed along itsouter circumference. The first indexing ridge is located at a homeposition and the second indexing ridge is spaced from the first indexingridge around the outer circumference of the keyed section by an angle α.The angle α is related to the type of anesthetic agent to which thebottle adapter will be applied. In the preferred embodiment of theinvention, the angle α between the pair of indexing ridges is the sameas the angle between the protrusions on the anesthetic bottles, asdetermined by the ISO standard.

The bottle adapter includes an adapter valve assembly that is positionedwithin the interior of the bottle adapter. The adapter valve assembly ismovable between an open position and a closed position to regulate theflow of anesthetic agent from the anesthetic bottle to which the bottleadapter is mounted. Specifically, the adapter valve assembly includes anelongated valve stem having a valve head formed on one end. The valvehead includes a conical sealing surface that engages a correspondingsealing seat formed on an annular flange extending into the interior ofthe bottle adapter. The valve head is biased into a closed position by aspring.

The outer diameter of the bottle adapter includes a probe section. Theprobe section is joined to the keyed section. The probe section isdefined at its outer edge by a top lip. The top lip is used to positiona sealing ring surrounding the outer circumference of the probe section.

The bottle adapter of the filling system of the present invention issized to mate with a filling station mounted to the anestheticvaporizer. The filling station is configured to receive only one type ofbottle adapter to insure that the proper anesthetic agent is deliveredto the anesthetic vaporizer.

The filling station includes a filler body that is secured to a mountingblock of the anesthetic vaporizer. The filler body defines an openinterior that is in communication with an internal cavity formed in themounting block. The internal cavity drains to the sump of the anestheticvaporizer such that the anesthetic agent can be directed to the sump.

The body of the filling station includes a filler spout formed on itsouter end. The filler spout includes a cylindrical outer wall having aseries of indexing grooves formed therein. The indexing grooves formedon the outer wall of the filler spout are positioned at an anglerelative to each other around the circumference of the filler spout. Theangle between the indexing grooves is based upon the ISO standard andthe type of anesthetic agent to be discharged into the anestheticvaporizer including the filling station. Preferably, the indexinggrooves each includes a recessed top edge surface that allows a user ofthe anesthetic vaporizer to quickly identify the position of theindexing grooves on the filling station.

The filling station includes a filler valve assembly that is movablebetween an open position and a closed position. When the filler valveassembly is in the closed position, anesthetic agent is prevented fromdraining into the internal sump of the anesthetic vaporizer whichprevents the wrong anesthetic agent being poured into the vaporizer froman open bottle without the presence of a correct bottle adapter.

In accordance with one aspect of the invention, the filler valveassembly includes a valve body having a conical sealing surface. Theconical sealing surface is biased into contact with a seal formed nearthe bottom edge of the filler body. The interaction between the conicalsealing surface of the valve body and the seal provides a liquid-tightseal to prevent anesthetic agent from inadvertently being dispensed intothe anesthetic vaporizer.

The filler valve assembly further includes a centrally locatedstationary activation rod that is immovably located within the fillerbody, along the centerline of the filling station. The activation rod issecured to a mounting block, which in turn is mounted to the innersurface of the filler body. The mounting block includes a series ofcylindrical openings that allow anesthetic agent to flow past theotherwise solid mounting block.

The valve body of the filler valve assembly includes a plurality ofprojecting legs that each extend through one of the cylindrical openingsformed in the mounting block. In this manner, the valve body extendspast the stationary mounting block such that the protruding legs andvalve body are movable relative to the stationary mounting block andstationary fixed activation rod.

A bias spring is positioned to urge the valve body into contact with theseal to prevent inadvertent filling of the anesthetic vaporizer with asupply of anesthetic agent. As described, the implementation of thefixed activation rod eliminates the dependency on relative spring ratesbetween the movable valve body of the vaporizer and the adapter valveassembly of the bottle adapter.

In accordance with the present invention, the filling system allows thebottle adapter to be securely coupled to the filling station as follows.Initially, the bottle adapter is attached to the correct type ofanesthetic bottle. The interaction between the mounting slots formed inthe bottle adapter and the protrusions on the anesthetic agent bottleinsure that the bottle adapter is used upon only the correct type ofanesthetic agent.

Once the bottle adapter has been installed, the bottle adapter isbrought into engagement with the filling station. As the bottle adapteris inserted into the filling station, the indexing ridges on the bottleadapter are brought into engagement with the indexing grooves formed inthe filling station. If the indexing grooves and indexing ridges match,the bottle adapter can be fully inserted into the filling station aswill be described. However, if the indexing grooves do not match theindexing notches, the bottle adapter is prevented from fully enteringinto the filling station.

If the bottle adapter is correct for the anesthetic vaporizer, thebottle adapter is inserted further into the filling station. As thebottle adapter is inserted, the sealing ring formed around the probesection of the bottle adapter engages a smooth inner surface formedwithin the filler body of the filling station. The interaction betweenthe sealing ring and the smooth inner surface provides a gas-tight sealto prevent built-up gas within the anesthetic vaporizer from beingreleased to atmosphere.

As the bottle adapter is moved further into engagement with the fillingstation, the top lip of the bottle adapter contacts the projecting legsformed on the valve body of the filler valve assembly. Slightly furthermovement of the bottle adapter causes the bottle adapter to move thevalve body away from the seal and open the filler valve assembly.

In another aspect of the invention, the dimensions of the bottle adapterand filling station are selected such that when the bottle adapterinitially opens the filler valve assembly, the top end of the stationaryactivation rod is spaced slightly from a recessed face surface formed onthe valve head of the adapter valve assembly. Thus, the filler valveassembly opens prior to opening of the adapter valve assembly.

Further movement of the bottle adapter into the filling station resultsin the stationary activation rod moving the valve head of the adaptervalve assembly to an open position. When in the open position,anesthetic agent can flow through the bottle adapter and into thefilling station.

As can be understood by the above description, the sealing ring formedaround the bottle adapter provides for a gas seal prior to opening ofeither the adapter valve assembly or the filler valve assembly.Additionally, the interaction between the keyed section of the bottleadapter and the filler spout of the filling station insure the propertype of anesthetic agent is being dispensed prior to opening of eithervalve assembly within the filling system

If the correct bottle adapter is being used, the invention insures thatthe filler valve assembly opens prior to the adapter valve assembly suchthat any discharged anesthetic agent is able to flow into the anestheticvaporizer.

In accordance with yet another aspect of the present invention, thestationary activation rod can include an internal passageway having afirst opening and a second opening. The first and second openings of theactivation rod are positioned on opposite sides of the seal created bythe valve body. This establishes a vent path to the sump for draining ofanesthetic agent from the vaporizer such that with the drain plugopened, and the filler cap loosened, venting of the sump isaccomplished, facilitating drainage.

In another aspect of the invention, the anesthetic vaporizer can includea colored indicator mark, label, feature or cover near the fillingstation that indicates the type of anesthetic agent to be dispensed intothe vaporizer. The color of the indicating mark on the anestheticvaporizer directly corresponds to the color of the bottle adapter to beused with the correct type of anesthetic agent. The positioning of suchcolored marks, features or components directly adjacent to the filler ischosen to present to the operator a direct color contrast wit h thebottle adapter in the event that the incorrect adapter is offered up tothe vaporizer filler.

Various other features, objects and advantages of the invention will bemade apparent from the following description taken together with thedrawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawings illustrate the best mode presently contemplated of carryingout the invention.

In the drawings:

FIG. 1 is a perspective view illustrating an anesthetic vaporizerfilling system of the present invention as used with an anestheticvaporizer;

FIG. 2 is a side view of a bottle adapter for use in the anestheticvaporizer filling system of the present invention;

FIG. 3 is a perspective view of the bottle adapter;

FIG. 4 is a partial cutaway perspective view of the bottle adapter shownin FIG. 3;

FIG. 5 is a back, perspective view showing the interior of the bottleadapter;

FIG. 6 is a section view taken along line 6—6 of FIG. 2;

FIG. 7 is a top view of the bottle adapter illustrating a pair ofindexing ridges;

FIG. 8 is a magnified section view illustrating the area shown by line8—8 in FIG. 6;

FIG. 9 is a perspective view of a filling station included on ananesthetic vaporizer that receives the bottle adapter;

FIG. 10 is a perspective, partial section view of the filling station ofFIG. 9;

FIG. 11 is a top view of the filling station illustrated in FIG. 9;

FIG. 12 is a section view of the filling station of the anestheticvaporizer filling system of the present invention;

FIG. 13 is a partial section view illustrating a filler cap used toclose the filling station of FIG. 12 when the filling station is notreceiving a bottle of anesthetic agent;

FIG. 14 is a section view illustrating the bottle adapter and fillingstation in their separated position;

FIG. 15 is a section view illustrating the bottle adapter being insertedinto the filling station and the opening of the filler valve assemblyprior to opening of the adapter valve assembly;

FIG. 16 is a magnified view of the area illustrated by line 16—16 inFIG. 15;

FIG. 17 is a section view illustrating the bottle adapter and fillingstation in a filling position;

FIG. 18 is a section view of a second embodiment of a filling stationconstructed in accordance with the present invention; and

FIG. 19 is a section view illustrating the second embodiment of thefilling station allowing anesthetic agent to be transferred from abottle joined to the bottle adapter.

DETAILED DESCRIPTION OF THE INVENTION

Referring first to FIG. 1, the present invention relates to ananesthetic vaporizer filling system 7 for connecting an anestheticbottle 8 to a vaporizer 9 for filling the internal slump within thevaporizer 9 with anesthetic agent contained within the anesthetic bottle8. The drawings and description of the present invention illustrate thefilling system used to accomplish this function. For ease ofunderstanding, the features of the anesthetic bottle 8 and the actualanesthetic vaporizer 9 are not shown in the Figures, since these twocomponents are available in many types of configurations and do not formpart of the present invention.

FIGS. 1-8 illustrate a bottle adapter 10 that forms part of theanesthetic vaporizer filling system of the present invention. The bottleadapter 10 is configured for attachment to the anesthetic bottle 8 thatincludes ISO 5360:1993 agent-specific features. The bottle adapter 10can be attached and removed from the anesthetic bottle 8 such that theanesthetic vaporizer filling system of the present invention can beutilized repeatedly with anesthetic bottles,

Referring now to FIG. 2, the bottle adapter 10 includes a lower, screwcap portion 12 and an upper, probe portion 14. The screw cap portion 12defines an open interior 16, as shown in FIG. 6. The open interior 16 issized to receive the threaded mouth of an anesthetic bottle and guidethe threaded mouth of the anesthetic bottle into engagement withagent-specific internal threads 18. The agent-specific threads 18 areconfigured to receive a specific type of anesthetic agent such that thebottle adapter 10 can be screwed onto the top of only one type ofanesthetic bottle.

As can be seen in FIGS. 5 and 6, the screw cap portion 12 includes apair of agent-specific receiving slots 20. The receiving slots 20 extendlongitudinally into outer wall 22 from a first end 24 of the screw capportion 12. The receiving slots 20 are sized to receive protrusionsformed on the collar of the anesthetic bottle. The protrusions formed onthe collar of the anesthetic bottle are spaced from each other by anangle dictated by the type of anesthetic agent contained within thebottle. Thus, the angle between the protrusions on the anesthetic bottleindicates the type of anesthetic agent contained within the specificbottle.

As illustrated in FIG. 5, the receiving slots 20 are spaced around thecylindrical outer circumference of the screw cap portion 12 by aspecific angle. The angle between the receiving slots 20 corresponds tothe agent-specific angle between protrusions on the anesthetic bottle.The corresponding angle between the protrusions on the anesthetic bottleand the slots 20 insures that the bottle adapter 10 can be installed ononly the correct type of anesthetic agent.

In addition to including the receiving slots 20, the bottle adapter 10is colored depending upon the type of anesthetic bottle upon which itwill be used. Under the ISO standard, the anesthetic agent Isoflurane iscolored purple, the anesthetic agent Halothane is colored red, theanesthetic agent Enflurane is colored orange and the anesthetic agentSevoflurane is colored yellow. The bottle adapter 10 is preferablyformed from nylon and colored in accordance with the ISO standard.

Referring back to FIG. 2, the screw cap portion 12 includes a series ofclosely spaced ribs 26 that provide a gripping surface for the screwingmotion required to attach the bottle adapter 10 to the threaded mouth ofan anesthetic bottle.

As shown in FIG. 6, the screw cap portion 12 is integrally formed withthe probe portion 14. The probe portion 14 has an outer diametersignificantly less than the screw cap portion 12. The outer diameter ofthe bottle adapter 10 decreases from the screw cap portion 12 to theprobe portion 14 and forms a first shoulder 28 and a second shoulder 30.

As can best be seen in FIG. 2, the probe portion 14 includes a keyedsection 32 that extends from the shoulder 30 to an upper end 34. Thekeyed section 32 includes a smooth outer surface 36 that defines anouter diameter of the keyed section 32. As illustrated in FIGS. 2 and 3,the keyed section 32 includes a pair of indexing ridges 38 a and 38 bthat extend outward from the smooth outer surface 36. The indexingridges 38 a and 38 b are used to insure the correct type of anestheticagent is used with the anesthetic vaporizer, in a manner to be describedin greater detail below.

As can be seen in FIG. 7, the indexing ridge 38 a protrudes from theouter surface 36 and is separated from the indexing ridge 38 b by theangle α. In the embodiment of the invention illustrated in FIG. 7, theangle α is 140°, which is the angle assigned to the anesthetic agentIsoflurane. The angle α between the indexing ridges 38 a and 38 b variesdepending upon the type of anesthetic agent contained within theanesthetic bottle to which the bottle adapter 10 is attached. Forexample, the angle α is 160° for the anesthetic agent Halothane, theangle α is 200° for the anesthetic agent Enflurane and the angle α is230° for the anesthetic agent Sevoflurane. These four examples are meantfor illustrative purposes only, since the angle α between the indexingridges 38 a and 38 b is set for each of the specific anesthetic agentscurrently available. This angle also corresponds to the angle betweenthe protrusions on the collar of an anesthetic bottle as set by ISO5360:1993. As can be seen in FIG. 3, the indexing ridges 38 a and 38 bare generally aligned with the receiving slots 20.

As can be seen in FIG. 7, the indexing ridge 38 a has a width greaterthan the width of the indexing ridge 38 b. As can be seen in FIG. 9, thecorresponding indexing groove in the vaporizer filler is a frontallylocated indexing groove that is positioned in the same place for eachtype of anesthetic agent. The wide indexing ridge 38 a is aligned with aprominent ridge on the screw cap portion for all anesthetic agents,which may be easily and conveniently located for alignment with thegroove in the front of the filler. The position of the indexing ridge 38b around the keyed section 32 with respect to the indexing ridge 38 avaries depending upon the type of anesthetic agent being used.

Referring back to FIGS. 2 and 3, the probe portion 14 includes anadapter probe section 40 that extends from the upper edge 34 of thekeyed section 32 to a top edge 42. The adapter probe section 40 has anouter diameter that is slightly less than the outer diameter of theouter surface 36 of the keyed section 32.

Referring now to FIG. 6, the outer wall 44 of the adapter probe section40 defines an open interior that receives an end piece 46. The end piece46 is defined by a cylindrical outer wall including a top lip 50. Thecylindrical outer wall is sized to be received within the open areadefined by the outer wall 44.

Referring now to FIG. 8, the end piece 46 includes a sealing ring 52around its outer circumference. The sealing ring 52 is entrapped betweenthe top lip 50 and the top edge 54 of the outer wall 44. The sealingring 52 provides for a gas-tight seal between the probe portion 14 andthe anesthetic vaporizer filling station, as will be described in muchgreater detail below.

As illustrated in FIG. 8, the outer wall 44 includes an inwardlyextending annular flange 56. The annular flange 56 supports the bottomedge 58 of the end piece 46. In the preferred embodiment of theinvention, both the bottle adapter 12 and the end piece 46 are formedfrom nylon. The end piece 46 is sized such that the end piece 46 can beultrasonically welded or otherwise bonded to the outer wall 44 of theadapter probe section 40 to form a continuous member.

The annular flange 56 includes a conical seat 60 formed at its inneredge. The conical seat 60 generally defines an opening that is incommunication with the open passageway 62 defined by the end piece 46.As illustrated in FIG. 6, the opening defined by the flange 56 isaligned with the open interior 64 such that anesthetic agent can flowfrom the anesthetic bottle through the probe portion 14 and out of thebottle adapter 10 through the end piece 46.

Referring now to FIGS. 4 and 6, the bottle adapter 10 includes anadapter valve assembly 66 that is movable between an open position and aclosed position to control the flow of anesthetic agent from theanesthetic bottle to which the bottle adapter 10 is attached. Theadapter valve assembly 66 includes an elongated valve stem 68 thatextends from a first end 70 to a second end 72. The second end 72 of thevalve stem 68 includes a valve head 74. The valve head 74 is defined bya cylindrical outer surface 76 that is joined to a conical sealingsurface 78, as illustrated in FIG. 4. As can be seen in FIG. 8, theouter surface 76 has a diameter greater than the diameter of the openingformed by the flange 56, which prevents the valve head 74 from passingthrough the opening defined by the flange 56. The conical sealingsurface 78 formed on the valve head 74 contacts the conical seat 60 toprovide a seal when the valve stem 68 is biased into contact with theflange 56.

Referring back to FIGS. 4 and 6, the valve head 74 further includes aplurality of guide fingers 80 that depend from the outer surface 76. Theguide fingers 80 each include a lateral guide surface 82 that contactsthe inner surface 83 defining the open interior 62 to guide the valvehead 74 during its opening and closing movement. The guide fingers 80are designed to maintain continuity of the single flow passage aroundthe open interior 62 of the bottle adapter and act with an angle ofoperation of 15 to 35 degrees from vertical to allow gravity to assistin separating liquid and gas during the filling process.

Referring back to FIGS. 4 and 6, the adapter valve assembly 66 is biasedto a closed position by a bias spring 84. The bias spring 84 has a firstend in contact with the valve head 74 and a second end supported withina mounting cage 86. The mounting cage 86 includes three support legs 88that extend upward and are joined to an annular flange 90. The annularflange 90 is supported at the top of the agent-specific threads 18. Ascan be seen in FIG. 6, the first end 70 of the valve stem 68 extendsthrough a central opening 92 such that the entire valve stem 68 can moverelative to the stationary mounting cage 86. As illustrated in FIG. 4,the annular flange 90 of the mounting cage 86 defines a central opening94 that is aligned with the open interior 64 such that the anestheticagent can flow from the anesthetic bottle through the bottle adapter 10and out of the end piece 46.

Referring back to FIG. 6, a resilient washer 96 is positioned in contactwith the annular flange 90 to provide a seal between the annular flange90 and an anesthetic bottle. In this manner, the anesthetic agent withinthe anesthetic bottle is prevented from flowing out of the first end 24of the bottle adapter 10.

In FIGS. 2-8, the bottle adapter 10 that forms half of the anestheticvaporizer filling system of the present invention has been described.Referring now to FIGS. 9-12, the second half of the anesthetic vaporizerfilling system of the present invention will now be described. Thesecond half of the filling system is a unique filling station 98associated with the anesthetic vaporizer 9. The filling station 98 isconfigured to receive the bottle adapter 10 and allow the anestheticagent to be discharged from the anesthetic bottle 8 attached to thebottle adapter and fill and internal sump within the vaporizer, as shownin FIG. 1.

As can be seen in FIGS. 9 and 10, the filling station 98 is positionedon a mounting block 100 positioned within the anesthetic vaporizer. Asillustrated in FIG. 12, the mounting block 100 includes an internallybored passageway 102 that leads to the internal sump of the vaporizer.The mounting block 100 further includes an internal cavity 104 that isbored from the otherwise solid mounting block 100. The internal cavity104 is defined by a generally cylindrical outer wall 106 and ispositioned at an angle relative to vertical. The outer wall 106 isjoined to a conical wall 108 that in turn is joined to a cylindricallower wall 110. The lower wall 110 defines a spring cavity 112 that isin fluid communication with the passageway 102.

Referring now to FIGS. 10 and 12, the filling station 98 is defined by afiller body 114. The filler body 114 includes an attachment flange 116having a plurality of attachment holes 118 that allow the filler body tobe securely attached to the mounting block 100, as best illustrated inFIG. 9. Referring back to FIGS. 10 and 12, the filler body 114 is ametallic member generally defined by a cylindrical outer wall 120 thatdefines open interior 122. The open interior 122 receives a portion of afiller valve 124, as will be described in much greater detail below.

The filler body 114 defines a filler spout 126 configured to direct andreceive the keyed section 32 of the bottle adapter. Specifically, thefiller spout 126 is defined by a cylindrical outer wall 128 including atop edge 130. The inner circumference of the outer wall 128 correspondsto the outer diameter of the smooth outer surface 36 of the keyedsection 32, as illustrated in FIG. 2. Thus, when the bottle adapter 10is inserted into the filling station 98, the outer surface 36 contactsthe inner surface 132 of the outer wall 128.

In order to accommodate the protruding indexing ridges 38 a and 38 bformed on the bottle adapter 10, the filler spout 126 of the fillingstation 98 includes a pair of indexing grooves 134 as shown in FIGS. 9and 10. The indexing grooves 134 are spaced by the same angle α thatdefines the spacing between the indexing ridges 38 on the bottleadapter, as illustrated in FIG. 7.

Referring back to FIGS. 9 and 10, each of the indexing grooves 134 aredefined by a wall portion 136. The wall portion 136 has a thickness lessthan the thickness of the outer wall 128 such that the indexing groove134 is formed by the difference in diameter between the inner surface132 of the outer wall 128 and the inner surface 138 of the wall portion136. In addition to having a thickness less than the outer wall 128,each of the wall portions 136 defines a top end 140 spaced slightlybelow the top edge 130 of the outer wall 128. The spacing between thetop edge 140 and the top edge 138 provide the user with a visualindication of the location for each of the indexing grooves 134.

Referring now to FIG. 12 and FIG. 14, the inner diameter of the openinterior 122 is slightly less than the inner diameter of the fillerspout 126 such that the probe section 40 of the bottle adapter 10 can beinitially inserted into the filling station 98 without resistive forcedue to compression of the seal 52 against the walls of the filler spout126.

Referring now to FIGS. 10 and 12, the filler valve assembly 124 includesa valve body 142. The valve body 142 includes a lower section 144 thatis surrounded by a bias spring 146. The bias spring 146 is supported atits first end with the spring cavity 112 and is in contact with thevalve body 142 at its second end. In this manner, the bias spring 146urges the valve body 142 into the closed, bias position illustrated inFIG. 12. A resilient seal 148 is positioned between the filler body 114and a conical sealing surface 150 formed on the valve body 142. The seal148 prevents the flow of an anesthetic agent into the internal cavity134 until the filler valve 124 has been opened.

The filler valve body 142 further includes a plurality of projectinglegs 152. The projecting legs 152 extend into the open interior 122 andare each defined by a top edge 154. As can be seen in FIGS. 10 and 11,each of the projecting legs 152 extends through a cylindrical opening156 formed in a stationary mounting block 158. The mounting block 158 issecured to the inner surface 159 of the outer wall 120 and is stationarywithin the open interior 122.

As illustrated in FIGS. 10 and 12, the mounting block 158 includes astationary activation rod 160. The stationary activation rod 160 issecured to the mounting block 158 and extends along the center axis ofthe filler body 114, as illustrated in FIG. 11. Since the stationaryactivation rod 160 is secured to the mounting block 158, the activationrod 160 does not move during operation of the filler valve 124.

Referring now to FIG. 12, the lower end 162 of the activation rod 160 isreceived within a guide cavity 164 formed in the lower section 144 ofthe valve body 142. The interaction between the guide cavity 164 and thestationary rod 160 guides the movement of the valve body 142 duringopening and closing of the filler valve assembly 124.

Referring now to FIG. 13, thereshown is a filler cap 166 that can beinstalled onto the filling station 98 when the fling station 98 is notreceiving a bottle of anesthetic agent. The filler cap 166 includes anouter surface that can be grasped by a user to attach the filler cap166. The filler cap 166 includes a series of internal threads 170 thatengage corresponding external threads 172 formed on the filler spout126, as illustrated in FIG. 12. The outer threads 172 extend along thefiller spout 126 until they reach a rim 174. The rim 174 includes aconical sealing surface 176. The conical sealing surface 176 receives aresilient sealing ring 178 formed near the bottom edge of the filler cap166, as shown in FIG. 13. The interaction between the sealing ring 178and the conical sealing surface 176 provides a seal for the fillingstation 98 when an anesthetic agent is not being used. The filler cap166 therefore prevents contamination from the environment and preventscontaminating debris from entering into the filler spout 126. In thepreferred embodiment of the invention, the filler cap 166 is permanentlyattached to the vaporizer by a flexible cord that prevents the fillercap 166 from being lost.

Referring now to FIGS. 14-17, the method and steps required to fill theanesthetic vaporizer using the anesthetic vaporizer filling system ofthe present invention will now be described. When it is desired to fillthe vaporizer with more liquid anesthetic agent, the bottle adapter 10is attached to the threaded top end of the anesthetic bottle.Specifically, the threaded end of the anesthetic bottle is receivedwithin the agent-specific threads 18 formed in the bottle adapter 10. Asthe bottle is screwed into registration with the threads 18, the top endof the bottle contacts the resilient washer 96 to provide a liquid tightseal between the bottle adapter 10 and the anesthetic bottle. Asdescribed, the receiving slots 20 formed in the bottle adapter 10correspond to protrusions contained on the anesthetic bottle to insurethat the correct type of bottle adapter can only be installed upon thecorrect type of anesthetic bottle.

Once the bottle adapter 10 has been securely attached to the anestheticbottle, the bottle adapter 10 can be inserted into the filling station98, as illustrated in FIG. 14. As can be seen in FIG. 4, the bottleadapter 10 includes a protruding visual guide 180 that is aligned withthe primary receiving slot 20. The visual guide 180 allows the user toeasily identity a known location on the bottle adapter 10. Once the userhas identified the visual guide 180, the bottle adapter 10 is rotateduntil the visual guide 180 is aligned with the lower indexing groove 134formed in the filler spout 126, as shown in FIG. 14. As described, eachof the indexing grooves 134 is defined by a top edge 140 recessed fromthe top edge 130 of the filler spout 126 to aid in the alignment of thebottle adapter 10 with the filling station 98.

Once the bottle adapter 10 has been aligned, the bottle adapter 10 ismoved into engagement with the filling station 98. In the preferredembodiment of the invention, the width B of the end piece 46 (FIG. 6) isless than the diameter of the filler spout 126, as defined by the innersurface 132. Thus, when the bottle adapter 10 is initially brought intoengagement with the filing station 98, the seal 52 does not causeresistive force against the inner surface 132 of the filler spout 126.

As the bottle adapter 10 continues its movement into the filling station98, the indexing ridges 38 a and 38 b of the bottle adapter are receivedwithin the corresponding indexing grooves 134 formed on the filler spout126. If the proper bottle adapter 10 is being utilized for the fillingstation 98, the interaction between the indexing ridges 38 a and 38 band the indexing grooves 134 allow the bottle adapter 10 to be movedfurther into engagement with the filling station 98. However, if thebottle adapter 10 is incorrect for the filling station 98, theinterference between the indexing ridges 38 a and 38 b of the bottleadapter 10 and the indexing grooves 134 of the filling station 98 willprevent further movement.

After the indexing ridges 38 a and 38 b of the bottle adapter arereceived within the corresponding indexing grooves 134 formed on thefiller spout 126, the sealing ring 52 contacts the inner surface 159 ofthe outer wall 120. The interaction between the sealing ring 52 and theinner surface 159 provides a gas-tight seal. The gas-tight seal createdby the sealing ring 52 prevents the gas pressure within the vaporizerfrom being vented to atmosphere when the filler valve assembly 124 isopened. It is important to note that the dimensions of the fillingsystem components are selected such that neither the adapter valveassembly 66 nor the filler valve assembly 124 opens prior to the keyedinteraction between the bottle adapter 10 and the filling station 98 andcreation of the gas-tight seal caused by the contact of sealing ring 52and inner surface 159. Therefore, anesthetic agent is not released fromthe anesthetic bottle prior to proper identification of the type ofanesthetic agent being dispensed, and the creation of a gas tight sealenclosing the fluid path during the filling process.

Once the indexing ridges 38 a and 38 b are received within thecorresponding indexing grooves 134, the bottle adapter 10 is movedfurther into the filling station 98, as shown in FIGS. 15 and 16. Duringthis movement, the top lip 50 of the bottle adapter 10 contacts the topedge 154 of each projecting leg 152. The further movement of the bottleadapter 10 pushes the entire valve body 142 downward against the biasspring 164. As the valve body 142 moves, the conical sealing surface 150moves away from the seal 148.

As shown in FIG. 12, the distance F from the top end 184 of theactivation rod 184 to the top edge 130 of the filler spout 126 and thedistance D from the top edge 154 of each projecting leg 152 to the topedge 130 are selected such that the filler valve assembly 124 is openedprior to opening of the bottle adapter valve assembly 60. Referring backto FIG. 16, the top end 184 of the activation rod 160 remains spacedfrom the recessed face surface 185 of the valve head 74 as the fillervalve assembly 124 is opened. The recessed face surface 185 is located adistance G from the top edge 42 of the lip 50, as illustrated in FIG. 6.

As the valve body 142 moves away from the seal 148, the sealing ring 52prevents the release of pressure within the anesthetic vaporizer toatmosphere. The filling station 98 can therefore be used with highpressures in the vaporizer.

As the bottle adapter 10 continues to move downward into the fillingstation 98, the top end 184 of the stationary activation rod 160contacts the recessed face surface 185 of the valve head 74, as shown inFIG. 17. The stationary activation rod 160 pushes the valve head 74 awayfrom the annular flange 56 against the force of the bias spring 84.Thus, the stationary activation rod 160 causes the adapter valveassembly 66 to open and allows the anesthetic agent to flow into thefiling station 98 by the force of gravity.

Once the bottle adapter 10 has been completely positioned within thefilling station 98, as illustrated in FIG. 17, the top edge 130 of thefiller spout 126 contacts the second shoulder 30 to securely support thebottle adapter 10 and connected bottle as illustrated. In this position,both the bottle adapter valve assembly 66 and the filler valve assembly124 are open, which allows the anesthetic agent to flow freely into thesump of the anesthetic vaporizer.

Once the anesthetic bottle has been emptied, the bottle adapter 10 ismoved out of engagement with the filling station 98. During thismovement, the valve head 74 moves back into contact with the annularflange 56 to seal the bottle adapter 10. Further movement of the bottleadapter 10 out of the filling station 98 causes the conical sealingsurface 150 to engage the seal 148, thus closing the filler valveassembly 124. Finally, the sealing ring 52 leaves engagement from theinner surface 159 and the bottle adapter is completely removed. As canbe understood by this sequence of operation, during removal the adaptervalve assembly 66 is closed first to prevent the flow of any furtheranesthetic agent out of the bottle adapter. Since the filler valveassembly 124 is still open when the bottle adapter valve assembly 66closes, any anesthetic agent that has left the bottle can pass throughthe filler valve assembly 124 and into the vaporizer sump. On occasionswhere the adapter is removed too rapidly for this liquid to drain to thevaporizer, or when the vaporizer is so filled that the internal passagesof the bottle adapter 10 and filling station are entirely filled withliquid, liquid which cannot drain to the vaporizer remains in thegenerally upward facing open interior 122 of the filler valve body, andis captured by replacement of the filler cap 166.

In the embodiment of the invention illustrated, the bottle adapter 10 isdescribed as being removable from each anesthetic bottle to bedischarged. However, it is contemplated by the inventors that the bottleadapter 10 could be permanently attached to an anesthetic bottle whileoperating within the scope of the invention. Further, it is contemplatedby the inventors that the bottle adapter could be permanently affixed tothe anesthetic vaporizer or attached and stored in a removable manner tothe anesthetic vaporizer for attachment to the anesthetic bottle in thislocation. Further, it is contemplated by the inventors that the fillingstation 98 could include a band, label, feature or cover of colortypically associated with the type of anesthetic agent to be used. Thecolor-coding configuration for the filling station would be the same asthe ISO standard used on the bottle adapter 10.

Referring now to FIG. 18, thereshown is a second embodiment of a filingstation 187 of the present invention. The filling station 187 shown inFIG. 18 is useful with vaporizers that do not include high internalpressures and includes a filler body 186 and a stationary activation rod188. The activation rod 188 includes a sealing flange 190. The-sealingflange 190 engages a conical sealing surface formed on a valve body 194.The valve body 194 is movable relative to the activation rod 188 and isbiased into a closed position by the bias spring 196. The valve body 194includes a sealing ring 198 that engages the inner surface of the fillerbody 186 and provides a liquid seal on this surface over the entireoperating travel of the valve body 194. The valve body is guided overthe operating travel of the valve by the inner surface of the fillerbody 186. A flexible washer 200 contacts the top end of the bottleadapter when the bottle adapter is positioned within the filling station98, as illustrated in FIG. 19. The filling station 187, as shown in FIG.18, includes an identical filler spout 126, the features of which havebeen previously described.

As illustrated in FIG. 18, the center activation rod 188 includes anopen passageway 202 that extends between an upper opening 204 and alower opening 206. The upper opening 204 and the lower opening 206 arepositioned on opposite sides of the sealing connection between thesealing flange 190 and the sealing surface 192.

The open passageway 202 allows alternative internal passageways to beemployed within the vaporizer which require the passage of gas toequalize pressure across the filler valve, for example during drainingof the vaporizer by means of some completely separate drain passage. Theabove opening 204 is positioned such that liquid incorrectly poured intothe filler spout will preferentially drain out of the spout by means ofpassageway 207 rather than draining past the filler valve into thevaporizer. Additionally, the upper opening 204 is located in the side ofthe activation rod 188 rather than the end, so that any fluid ejectedfrom this port for any reason due to misuse of the vaporizer, is notdirected upwards, but harmlessly against the inner surface of the fillerbody 186.

The lower opening 206 connects to the internal cavity 104 which connectsto the open passageway 102 to direct the anesthetic agent to thevaporizer sump.

As illustrated in FIG. 19, the fixed center activation rod 188 functionsto move the valve head 74 to an open position to allow anesthetic agentfrom the bottle adapter 10 to enter into the filling station 98. Likethe first embodiment previously described, the filler valve assembly 204opens prior to the adapter valve assembly 66 as the bottle adapter 10 isbrought into engagement with the filling station 98. Thus, comparingFIG. 19 and FIG. 14, the fixed center activation rod 188 is equivalentto activation rod 160 of the first embodiment and the valve body 194including sealing ring 198 is together equivalent to valve body 142 ofthe first embodiment. The inner surface of the filler body 186, asregards guidance of the valve body 194, is equivalent to the lower part162 of activation rod 160 which guides the movement of the valve body142 in the first embodiment. The latter valve body 142 does not requirea sealing ring such as 198 since the equivalent to sealing over thetravel of the valve body 194 is provided by the fact that the valve body142 surrounds the guidance member in such a way that no additionalsealing over the guidance member is required.

Various alternatives and embodiments are contemplated as being withinthe scope of the following claims particularly pointing out anddistinctly claiming the subject matter regarded as the invention.

1. A removable adapter for a bottle containing an anesthetic agent, thebottle having a key member relating to the type of anesthetic agent inthe bottle, said adapter being suitable for insertion into to a fillingstation of an anesthetic vaporizer to connect the bottle to the fillingstation, said adapter comprising: a body member comprising a rigidportion which is lower when the adapter is mounted on an upright bottleand an upper rigid portion integrally joined to said lower portion, saidlower portion having a wall defining an open interior and containingmeans for removably mounting said adapter on the bottle, said lowerportion having means for engaging the key member on the bottle forallowing said adapter to be mounted on the bottle, said upper portionhaving a wall defining an open interior, said upper portion beinginsertable in the filling station of the anesthetic vaporizer to connectthe adapter to the filling station, said upper portion having a pair ofperipherally spaced indexing ridges on the exterior thereof, theperipheral spacing of said ridges relating to the type of anestheticagent in the bottle, said ridges engaging with complementary grooves insaid filling station to allow insertion of the upper portion into thefilling station when the type of anesthetic agent in the bottle isproperly matched to the vaporizer, said adapter having a visually ortactilely perceptible means on the exterior thereof aligned with one ofsaid indexing ridges for assisting in aligning the indexing ridges withthe complementary grooves to facilitate insertion of the upper portionof the adapter in the filling station; and a valve in said adapter,openable when said upper portion is inserted in the filling station toallow anesthetic agent to flow from the bottle into the filling station.2. The adapter of claim 1 wherein said visually or tactilely perceptiblemeans comprises a guide ridge on the exterior of said adaptor.
 3. Theadapter of claim 2 wherein said guide ridge is formed on said lowerportion of said adaptor.
 4. The adapter of claim 1 wherein said indexingridges differ in width.
 5. The adapter of claim 1 wherein the locationof said one of said indexing ridges having said visually or tactilelyperceptible means aligned therewith is fixed and the peripheral spacingof the other of the indexing ridges varies depending on anesthetic agenttype.
 6. The adapter of claim 1 wherein the key member has peripherallyspaced features, said engaging means on said lower portion includesperipherally spaced engagement means corresponding to the features andwherein said indexing ridges are peripherally spaced by the same spacingas said engagement means.
 7. The adapter claim of 6 wherein the featuresof said key members are protrusions and said feature engaging means onsaid adapter comprises receiving slots in said lower portion.
 8. Theadapter of claim 1 wherein said lower and upper portions are generallycylindrical and wherein said upper portion has an outer diameter lessthan that of said lower portion.
 9. The adapter of claim 1 wherein saidadapter is colored in accordance with the type of anesthetic agent. 10.The adapter of claim 1 wherein said adapter is formed of nylon.
 11. Theadapter of claim 1 wherein said upper portion includes an end piecehaving a top lip.
 12. The adapter of claim 11 wherein said upper portionfurther includes a sealing ring intermediate said upper portion and saidend portion for forming a seal between the adapter and the fillingstation when said upper portion is inserted in the filling station. 13.The adapter of claim 11 wherein the end piece is formed of nylon.